Hctcropiiccin ia . 173 



Taraxacum, one of which belongs to F. variabilis^ and the other to 

 P. sylvatica 



The two aecldia on Taraxacum have both been found by Mr. Soppitt, 

 who kindly sent me specimens ; one has numerous small clusters of 

 pseudoperidia scattered over the leaves = ^c. grevillei, Grove. This 

 Mr. Soppitt laid upon a plant of Taraxacum, and in a fortnight he 

 found the Taraxacum affected with Puccinia. I have repeated this 

 experiment with a^cidiospores found near King's Lynn with success. 



In the other ajcidium {F. sylvatica) the pseudoperidium occurs in 

 large clusters, and is the one described above. 



The teleutospore host-plants are those given by Schroter in Cohn's 

 " Krypt. Flor. von Schlesien," vol. iii. p. 328. 



Puccinia dioicse. Magnus. 



^Ecidiospores — Spermogonia in small crowded groups, yellow. 

 Pseudoperidia in one or many circles, crowded on roundish 

 spots, flat, with torn white edges. Spores orange-yellow, as 

 much as 25/^ in diameter. 



Uredospoi'es — Sori small, chestnut-brown, roundish. Spores glo- 

 bose, elliptical, or ovate, as much as 25/A long, pale brown, 

 echinulate. 



Teleutospores — Sori thick, roundish, persistent, black, pulvinate. 

 Spores clavate, apex much thickened, rounded or pointed, 

 constriction slight, base attenuated, smooth, brown, 

 35-55 X 17-20/X. Pedicels persistent, 40/A long. 



Synonyms. 



Puccinia dioica. Magnus, Tagebl. der Naturf. vers, zu MU?ichen 

 (1877), P- 200. Schrot., " Krypt. Flor. Schl.," p. 329. 

 j^cidiiim cirsii. D. C, " Flore fran(^.," vol. v. p. 94. 



^cidiospores on Carduus palustris, July — Professor J. VV. H. 

 Trail. 



Teleutospores on Carex dioica, davalliana. 



Biology. — Schroter worked out the biology of this species in 

 1880 ("Krypt. Flor. Schl.," vol. iii. p. Z'lP)^ by placing the teleuto- 

 spores of F. dioiccB on Cirsium oleracetiiii. Johanson and Rostrup, in 

 June, 1883, during an excursion in Jutland, found the ascidium on 

 C. palustris, lanceolatiiin, and arvcnse, growing in company with 

 F. dioicce. The teleutospores have not at present been found in 

 Britain, but Professor Trail found the tecidiospores in July. 



